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United States Patent | 5,266,370 |
Woodson ,   et al. | November 30, 1993 |
A centrifugally cast plastic pipe comprised of a polymer derived from monomers polymerized in bulk is provided. A pressurized cylindrical mold provides smooth inner and outer surfaces. Pipes with a wall thickness of from 1/8 inch to 3 inches and an outer diameter of 1 inch to 12 feet are provided.
Inventors: | Woodson; Charles S. (The Woodlands, TX); Darnall; Michael J. (Baton Rouge, LA); Deumite; Norman A. (Baton Rouge, LA) |
Assignee: | PTI/End-Corr, Inc. (The Woodlands, TX) |
Appl. No.: | 679862 |
Filed: | April 3, 1991 |
Current U.S. Class: | 428/36.92; 138/174; 138/DIG.7; 264/83; 264/311; 428/36.1; 428/36.9; 428/409 |
Intern'l Class: | B29C 041/04; F16L 009/12 |
Field of Search: | 428/36.9,36.92,409,36.1,34.5,36.4,36.3 264/310,311,82,83,270 138/DIG. 7,174,DIG. 2 |
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4918146 | Apr., 1990 | Matlack | 525/354. |
4988549 | Jan., 1991 | Meyer et al. | 428/36. |
Robert Burns, "Getting Started in DCPD RIM Molding," Plastics Technology, vol. 35, No. 3, Mar. 1989, pp. 62-69. R. Juran (ed.), Modern Plastics Encyclopedia, Mid-Oct. 1989 Issue, vol. 66, No. 11, McGraw-Hill, pp. 892-893, 901. |